Characterization of unconventional sand-based substrates for adsorption of micropollutants in nature-based systems

in Journal of Environmental Management (2022)

The focus of this study is the characterization of unconventional sand-based substrates used in our previous project EmiSûre, (Interreg Greater Region (German federal states Rhineland-Palatinate and ... [more ▼]

The focus of this study is the characterization of unconventional sand-based substrates used in our previous project EmiSûre, (Interreg Greater Region (German federal states Rhineland-Palatinate and Saarland, the Grand Duchy of Luxembourg, regions Wallonia and Lorraine from Belgium and France, respectively), 2017–2021). The project aimed to develop and test alternative, nature-based technologies for the elimination of micropollutants (MPs) from municipal wastewater. For the characterization, two approaches were chosen. In the first approach, adsorption kinetics with a single compound allowed a perception of the adsorption capacity of the studied substrates compared to conventional substrates (granular activated carbons). This knowledge was completed by the second approach: an implementation of the studied substrates in packed-bed columns, which treated a mixture of 27 MPs in tap water for 10 months. Additionally, all three substrates (bentonite sand, sand with 15% activated biochar and sand with 15% zeolite) were characterized for physical and chemical properties, and the microbial potential of the activated and non-activated biochar was examined. From the studies, it is clear that the sand with an admixture of activated biochar is the most efficient sorbent in terms of single compound adsorption in batch (dye) and adsorption of 27 MPs on packed-bed columns. In contrast to the two other substrates, it shows long-term stable removal efficiencies. In the packed-bed columns, 18 out of 27 compounds were removed on average with high efficiency (80–99%), which is impressive, if we consider the variety of the compounds examined (pharmaceuticals, herbicides, pesticides, etc.) and their removal in conventional treatments. Addi- tionally, adsorption models were created for the experimental data of all compounds adsorbed on the substrate with an admixture of activated biochar resulting in the best fit with the combined Langmuir-Freundlich model. These satisfying results suggest the application of the sand-based substrate with an admixture of activated biochar for further research and possibly upscale installations with the aim to offer and prove a reasonable and efficient alternative for MPs elimination from municipal wastewater. [less ▲]

Assessing the impact of micropollutants mitigation measures using vertical flow constructed wetlands for municipal wastewater catchments in the greater region: a reference case for rural areas

in Water Science and Technology (2022)

The present research aims at giving an approach to the issue of surface water contamination due to micropollutants in rural areas. The catchment of the Sûre river was selected as a reference case for the ... [more ▼]

The present research aims at giving an approach to the issue of surface water contamination due to micropollutants in rural areas. The catchment of the Sûre river was selected as a reference case for the Greater Region, characterized mainly by settlements with low population density, small water bodies and small- to medium-sized wastewater treatment plants (WWTPs). For these WWTPs, conventional technical solutions for micropollutants elimination are not suitable; therefore, an adapted mitigation strategy is needed to prevent the impact of micropollutants, especially during the dry season. As a suitable alternative to more intensive technologies, Constructed Wetlands (CW) in Vertical Flow (VF) configuration have been successfully tested over one-year period and the elimination rate of 27 micropollutants was quantified. Emission reduction by VF was then considered in a static mass balance model that calculates the longitudinal concentrations profile for the entire river catchment. The EmiSûre approach which focuses on river quality (concentrations of pollutants) instead of emitted loads, effectively allowed to simulate adopted measures a priori and resulted efficient to support decision-makers with WWTPs upgrade scenarios. [less ▲]

Bioremediation of 27 Micropollutants by Symbiotic Microorganisms of Wetland Macrophytes

in Sustainability (2022), 14(7), 3944

Background: Micropollutants in bodies of water represent many challenges. We addressedthese challenges by the application of constructed wetlands, which represent advanced treatmenttechnology for the ... [more ▼]

Background: Micropollutants in bodies of water represent many challenges. We addressedthese challenges by the application of constructed wetlands, which represent advanced treatmenttechnology for the removal of micropollutants from water. However, which mechanisms specificallycontribute to the removal efficiency often remains unclear. Methods: Here, we focus on the removalof 27 micropollutants by bioremediation. For this, macrophytesPhragmites australis,Iris pseudacorusandLythrum salicariawere taken from established wetlands, and a special experimental set-up wasdesigned. In order to better understand the impact of the rhizosphere microbiome, we determinedthe microbial composition using 16S rRNA gene sequencing and investigated the role of identifiedgenera in the micropollutant removal of micropollutants. Moreover, we studied the colonizationof macrophyte roots by arbuscular mycorrhizal fungi, which are known for their symbiotic rela-tionship with plants. This symbiosis could result in increased removal of present micropollutants.Results: We foundIris pseudacorusto be the most successful bioremediative system, as it removed22 compounds, including persistent ones, with more than 80% efficiency. The most abundant generathat contributed to the removal of micropollutants werePseudomonas, Flavobacterium, Variovorax,Methylotenera, Reyranella, AmaricoccusandHydrogenophaga.Iris pseudacorusexhibited the highest colo-nization rate (56%). Conclusions: Our experiments demonstrate the positive impact of rhizospheremicroorganisms on the removal of micropollutants. [less ▲]

QUANTIFICATION OF MICROPOLLUTANT REMOVAL MECHANISMS IN VERTICAL-FLOW CONSTRUCTED WETLANDS: OUTCOME OF THE ‘EMISÛRE’ PROJECT

in Book of Abstracts - "9th International Symposium on Wetland Pollutant Dynamics and Control - WETPOL 2021" (2021, September 15)

Quantification of removal mechanisms in vertical flow constructed wetlands as nature based solutions for treatment of wastewater effluent

Poster (2021, March 18)

Assessment of the production of biodiesel from urban wastewater-derived lipids

in Resources, Conservation and Recycling (2020), 162

Production of biodiesel is one of the most important European targets within renewables for the future. To consider biodiesel a feasible alternative to fossil fuel, unconventional resources need to be ... [more ▼]

Production of biodiesel is one of the most important European targets within renewables for the future. To consider biodiesel a feasible alternative to fossil fuel, unconventional resources need to be exploited. This review aims to provide up-to-date knowledge on the existing reuse of lipids from urban wastewater to produce biodiesel. Lipids are readily removed by mixed microbial populations during wastewater treatments in sewage plants. Assessment results on potential annual European market supply indicate 3 – 414 104 tons (min for activated and max for grease trap sludge) of potentially extractable biodiesel from wastewater and an expected biodiesel demand of 14.8 106 tons. Considering the prospect of transforming sewage plants into biorefineries, we may cover on average 1.5, 6.2, 6.7 and 24.4% of activated, primary, scum and grease trap sludge respectively, of the European biodiesel market from wastewater-derived lipids. In addition, by implementing an optimized biotechnology selector, the overall biodiesel yield could be higher due to increased lipid incorporation into microbial biomass. This is not an insignificant amount and, if efficiently implemented, could represent an exploitable resource for biofuel production, an important and desired step towards a circular economy. The technology readiness level is still very low. There are several challenges and possible drawbacks, e.g., biogas yield loss, substrate depletion, or formation of floating sludge. Finally, no definitive legislative barriers towards wastewater-derived lipids have been identified; however, quality criteria as well as waste status have to be defined. [less ▲]

WOW! Sewage is valuable!

Scientific Conference (2020, February)

There are market opportunities for raw materials from sewage, but for this the sewage treatment plants and the industry need alignment. This calls for a transition: sewage treatment plants need to switch ... [more ▼]

There are market opportunities for raw materials from sewage, but for this the sewage treatment plants and the industry need alignment. This calls for a transition: sewage treatment plants need to switch from treating sewage to producing valuable materials. On the other hand, market parties need to regard sewage as a valuable source instead of ‘dirty unsafe water’. Last but not least, the policies should better fit this new circular practice. To realize these opportunities WOW! aims to develop value chains for three different raw materials from sewage: cellulose, PHA bioplastics and lipids. [less ▲]

ROLE OF TARGETED BIOCHAR-ACTIVATION IN THE REMOVAL OF MACRO- AND MICROPOLLUTANTS FROM SECONDARY EFFLUENT WASTEWATER

in Book of Abstracts 8th International Symposium On Wetland Pollutant Dynamics and Control (2019, January 30)

Is a Vertical Flow Constructed Wetland a suitable polishing treatment for micropollutant removal in small and medium-sized WWTPs? A case of study

Poster (2018, October 02)

Is A Vertical Flow Constructed Wetland A Suitable Polishing Treatment For Micropollutant Removal In Medium-sized WWTPs? A Case Of Study

in 16th IWA Wetland System for Water Pollution Control, ICWS2018 (2018)